1. Field of Invention
The present invention relates to the technical field of shield machine, and more particularly to an earth pressure balance shield machine without disc cutter arrangement.
2. Description of Related Arts
At present, existing earth pressure balance shield machines in this country or aboard all utilize a disc cutter arrangement in their cutting system. In cylindrical shield machines, the disc cutter performs a circular movement; while in shield machines of rectangular, oval or other special shape, the disc cutter performs a planar movement through a crank linking arrangement, a swing arrangement or a profiling arrangement. Based on the geological condition and the engineering requirements, different types of cutting members such as hob, cutter or scraper are installed on the cutterhead. The cutting members move along with the cutterhead and no active rotation of the cutting members is allowed. Since the speed of action of the cutterhead is very low (a few rotation per minute), the linear velocity of cutting of the cutting members are then very low which limit the efficiency of cutting. Meanwhile, since the position of different cutting members on the cutterhead are varied, the linear velocity of cutting of different cutting members are varied greatly, therefore the operating life of different cutting members are varied greatly.